Oshi no Ko: Secrets behind Ruby and Aquamarine Hoshino's names, explored

Ruby and Aquamarine Hoshino as seen in Oshi no Ko
Ruby and Aquamarine Hoshino as seen in Oshi no Ko (Image via Doga Kobo)

Oshi no Ko anime began with B-Komachi idol Ai Hoshino at its center. For the most part, it seemed like the anime would focus on her struggle as a mother and an idol. However, the focus soon shifted to its protagonists, Ruby and Aquamarine Hoshino.

While Ruby seems like a normal name, Aquamarine evidently sounds very extravagant. The name stands out so much that even the protagonist was surprised he was given such a name. That said, why did Ai Hoshino name her children Ruby and Aquamarine?


Oshi no Ko: What do Ruby and Aquamarine Hoshino's names signify?

Ai Hoshino with her children in Oshi no Ko (Image via Doga Kobo)
Ai Hoshino with her children in Oshi no Ko (Image via Doga Kobo)

Both Aquamarine and Ruby Hoshino are the reincarnations of Ai's fans. In their previous lives, they were named Gorou Amamiya and Sarina Tendouji, respectively. Upon being born as Ai Hoshino's children, they were named Aquamarine and Ruby Hoshino.

Ruby Hoshino as seen in Oshi no Ko (Image via Doga Kobo)
Ruby Hoshino as seen in Oshi no Ko (Image via Doga Kobo)

Ai Hoshino herself had purple-colored eyes, and that eye color seemed to have split between her two children. Ruby was born with red-colored eyes, while Aquamarine with blue-colored eyes. Thus, Ai Hoshino must have named her children based on the gemstones that match the same colors as their eyes. Hence, Ruby and Aquamarine were named as such.

Aquamarine Hoshino as seen in Oshi no Ko (Image via Doga Kobo)
Aquamarine Hoshino as seen in Oshi no Ko (Image via Doga Kobo)

That said, Aquamarine Hoshino, himself believes that his name is psychologically damaging. Thus, he would have preferred that he switch places with Ruby. Moreover, he makes sure to ask people around him to call him Aqua instead of Aquamarine.


How fans reacted to Aquamarine Hoshino's name

Almost all Oshi no Ko fans found Aquamarine's name to be very odd. The name was not just very rare but also quite long, which made it even more questionable. Fans have since wondered why Ai Hoshino gave her son such a long name. She could have even named him Aqua, given that she herself called Aquamarine by that name in the first episode.

People found it odd that the name did not suit Aqua. He is someone who is determined to track down his biological father and get revenge on him for planning the murder of his mother. With such important tasks, the name Aquamarine feels really out of place. Thus, fans were glad that he had a nickname, i.e., Aqua.

In addition, several fans found it really funny that Aquamarine would canonically want to switch places with Ruby as he did not like his name. Even when Aquamarine was a baby, he was certain that he was set to have a tough time with a name like his. Thus, he wished that his role was switched with Ruby. However, as that was impossible, he decided to ask others to address him as Aqua.

Many Oshi no Ko fans found Aquamarine's name so odd that they were reluctant to read the manga because of it. Nevertheless, they pushed past that obstacle and continued with the series. Looking back, it seemed realistic that Ai named her son Aquamarine, considering that celebrities giving their children weird names is quite common.